On last night's episode of HBO's "Big Little Lies,"watchers simultaneously rejoiced — and winced — when Celeste (Nicole Kidman) hit her abusive husband Perry (Alexander Skarsgard) with a tennis racket in the dick.

In the aptly named episode “Burning Love,” Celeste rebuffs Perry’s advances because she doesn’t want to be late for the opening night of her BFF Madeline’s (Reese Witherspoon) musical “Avenue Q” — and she knows his play at seduction is a petty attempt to isolate her from her friends. When he predictably responds with violence, yanking her by the hair and taking his dick out — which the Internet is especially curious about — she grabs the closest object of defense, sending Perry to the hospital. He returns later, citing a “broken urethra.”

We couldn’t help but wonder, what even is a broken urethra, and could what looked to us like a light tap of a tennis racket have really caused it? Wasn’t Perry likely exaggerating the situation so he could hold it against Celeste later? “You’re lucky I didn’t kill you,” he tells her. “You could have done permanent damage.”

We asked Dr. Robert Caleb Kovell,assistant professor of Clinical Urology in Surgery at UPenn, to explain common penile injuries and what causes them.

You can’t break your urethra

First of all, you wouldn’t call it a “break,” Kovell explains. You can rip or tear your urethra — but it isn’t likely the impact from Celeste's racket could have caused it.

“It usually requires a significant amount of force,” Kovell explains, such as a “straddle injury” from horseback riding or a high-impact incident, such as a car crash.

Kovell notes that a urethral tear isn’t a tear in the skin, but within the urethra, beneath the skin. (The “pee hole,” if you will, that we see, is just the urethral opening, while the urethra itself is essentially an internal tube connecting the penis to the bladder.) This can lead to what’s called a urethral stricture, when scar tissue forms in the urethra and blocks the flow of urine.

You’d probably hurt the rest of your penis, as well

“It would be rare for someone to only injure the urethra and not suffer from a penile fracture too,” says Kovell.

While you can’t break your penis either, you’ve likely heard the phrase, which Kovell explains is in reference to a "penile fracture."This usually occurs during sex, when an erect penis slips out and hits against the partner’s pubic bone and the corpora cavernosa — internal cylinders in the penis that fill up with blood during an erection — can snap under pressure, and the hard outer covering will rip.

Maybe Perry has a sensitive penis, or maybe he's a (well-endowed) little liar. We don’t hope he gets well soon.